With sincere honesty, without legislation to force companies to do the right thing bike will not make safety improvements. They will make aesthetic improvements and functional additions but are not inclined to R&D the design. They make money just fine as is. So should cyclists rebel and not wear helmets? Sure go right a head if it suits you. Until that in which you get a head injury and finally realize some protection is better than none. You could be lucky fool who never wears a helmet as you do your "tour de France" through life and never hits your head. Good luck.
As a 'lucky fool' who's been riding bikes for over 60 years without serious injury I count my blessings and good luck to you, too.
The risk of a traumatic brain injury whilst cycling unhelmeted is estimated at around 0.41 per million hours travelled or, if I cycle for 2 hours a day, once every 3,300 years or so.
The figure for unhelmeted motor vehicle occupants is similar (0.46); I'll continue to do the little bit of driving I do also without a helmet.
The figure for pedestrians is a fair bit higher at 0.80 per million hours travelled - near enough to cycling for me to make a similar judgement - which leads me to my question:
As the risk whilst you're walking is greater than your risk when you're cycling will you also make a similar judgement - and wear a helmet whilst out perambulating?
(For motorcyclists it's 7.66 so I'll agree with your choice for that mode of travel)